Is the iPhone sufficiently awesome to justify its high price? Are there good low-cost smartphones? Ios or android?

My first question would be: how do you intend to use the device?

The two apps you mentioned are also available on Android, and I'm very happy with Evernote on my HTC Desire HD (I don't use Toodledo). So if your main use would be those apps along with the typical phone stuff (calls/text message/email/web browsing) then an Android device should be fine for you.

However, a high-end Android device gets close to the price range of an iPhone.